Adam Adam - 2 months ago 61
Android Question

Progress Bar with unzipping of file

I am trying to update a

progress bar
with unzipping of file in the sd card. My unzipping works fine but the
progress bar
does not appear. Here is my code in mainactivity:

private ProgressBar bar;

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);

bar = (ProgressBar) findViewById(R.id.progress);

String zipFilename = Environment.getExternalStorageDirectory() + "path to my zip file in sd card";
String unzipLocation = Environment.getExternalStorageDirectory() + "the output folder";




Decompress d = new Decompress(zipFilename, unzipLocation);
d.unzip();
}

public class Decompress {
private String _zipFile;
private String _location;
private int per = 0;



public Decompress(String zipFile, String location) {
_zipFile = zipFile;
_location = location;
_dirChecker("");
}
public void unzip() {
try {
ZipFile zip = new ZipFile(_zipFile);
bar.setMax(zip.size());
FileInputStream fin = new FileInputStream(_zipFile);
ZipInputStream zin = new ZipInputStream(fin);
ZipEntry ze = null;
while ((ze = zin.getNextEntry()) != null) {

Log.v("Decompress", "Unzipping " + ze.getName());
if(ze.isDirectory()) {
_dirChecker(ze.getName());
} else {
// Here I am doing the update of my progress bar

per++;
bar.setProgress(per);
FileOutputStream fout = new FileOutputStream(_location + ze.getName());
for (int c = zin.read(); c != -1; c = zin.read()) {

fout.write(c);
}
zin.closeEntry();
fout.close();
}
}
zin.close();
} catch(Exception e) {
Log.e("Decompress", "unzip", e);
}
}
private void _dirChecker(String dir) {
File f = new File(_location + dir);
if(!f.isDirectory()) {
f.mkdirs();
}
}

}
}

Answer

Your unzipping code is running on the Main/UI thread, thereby freezing the UI. You want to do the unzipping in a background thread using AsyncTask.

Example for your case:

 private class Decompress extends AsyncTask<Void, Integer, Integer> {

   private String _zipFile;   
   private String _location;
   private int per = 0;

   public Decompress(String zipFile, String location) {
       _zipFile = zipFile;     
       _location = location;      
       _dirChecker("");   
   }


    @Override
    protected Integer doInBackground() {
        try {
            ZipFile zip = new ZipFile(_zipFile);
            bar.setMax(zip.size());
            FileInputStream fin = new FileInputStream(_zipFile);
            ZipInputStream zin = new ZipInputStream(fin);
            ZipEntry ze = null;
            while ((ze = zin.getNextEntry()) != null) {

                Log.v("Decompress", "Unzipping " + ze.getName());
                if (ze.isDirectory()) {
                    _dirChecker(ze.getName());
                } else {
                    // Here I am doing the update of my progress bar

                    per++;
                    publishProgress(per);

                    FileOutputStream fout = new FileOutputStream(_location + ze.getName());
                    for (int c = zin.read(); c != -1; c = zin.read()) {
                        fout.write(c);
                    }
                    zin.closeEntry();
                    fout.close();
                }
            }
            zin.close();
        } catch (Exception e) {
            Log.e("Decompress", "unzip", e);
        }
        return totalSize;
    }

    @Override
    protected void onProgressUpdate(Integer... progress) {
        bar.setProgress(per); //Since it's an inner class, Bar should be able to be called directly
    }

    @Override    
    protected void onPostExecute(Integer... result) {
        Log.i("Completed. Total size: " + result);
    }
}
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